Applying a nanocomposite hydrogel electrode to mitigate electrochemical polarization and focusing effect in electrokinetic remediation of a Cu- and Pb-contaminated loess

Wenle Hu; Wen-Chieh Cheng; Yihan Wang; Shaojie Wen; Zhong-Fei Xue

doi:10.1016/j.envpol.2023.122039

Applying a nanocomposite hydrogel electrode to mitigate electrochemical polarization and focusing effect in electrokinetic remediation of a Cu- and Pb-contaminated loess

Environ Pollut. 2023 Sep 15:333:122039. doi: 10.1016/j.envpol.2023.122039. Epub 2023 Jun 17.

Authors

Wenle Hu¹, Wen-Chieh Cheng², Yihan Wang³, Shaojie Wen⁴, Zhong-Fei Xue⁵

Affiliations

¹ School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an, 710055, China. Electronic address: wenlehu@xauat.edu.cn.
² School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an, 710055, China. Electronic address: w-c.cheng@xauat.edu.cn.
³ School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an, 710055, China. Electronic address: wangyihan@xauat.edu.cn.
⁴ School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an, 710055, China. Electronic address: wenshaojie@xauat.edu.cn.
⁵ School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an, 710055, China. Electronic address: xuezhongfei@xauat.edu.cn.

PMID: 37336350
DOI: 10.1016/j.envpol.2023.122039

Abstract

Inappropriate handling of copper (Cu) and lead (Pb)-containing wastewater resulting from metallurgical and smelting industries in Northwest China encourages their migration to surrounding environments. Their accumulation causes damage to liver and kidney function. The electrokinetic (EK) technology is considered to be an alternative to traditional remediation technologies because of its great maneuverability. The EK remediation is accompanied by the electrode polarization and the focusing effect toward affecting removal efficiency. In this study, a nanocomposite hydrogel (NCH) electrode was proposed and applied to the EK remediation of Cu- and Pb-contaminated loess. The mechanical, adsorption capacity, adsorption kinetics, and electrochemical properties of the NCH electrode were investigated in detail, followed by microscopic analyses of Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDS), and Raman spectrometer. Results showed that the enhancement of the mechanical properties of the NCH electrode was attributed to the crosslinks of graphene nanoparticles, calcium alginate, and hydrogen bonds, while the Cu or Pb adsorption by the NCH electrode was in a chemisorption manner. The second layer formation might address the increase in adsorption capacity with increasing temperature. These results highlight the relative merits of the NCH electrode and verify the potential of applying the NCH electrode to the EK remediation of Cu- and Pb-contamianted loess.

Keywords: Adsorption capacity; Electrode polarization; Electrokinetic remediation; Focusing effect; Nanocomposite hydrogel electrode.